Note: I have changed the title of this post for the benefit of readers who are unfamiliar with the term ‘substance dualism’.
Many of our readers – especially among the regulars at Uncommon Descent – are substance dualists. That is, they believe that each of us has an immaterial mind or soul that constitutes our true self, and that the body, including the brain, is merely a vehicle “inhabited” and controlled by the mind or soul.
There are many problems with this idea, which is why it is rejected by most neuroscientists and philosophers. One of the most striking is the problem posed by the strange characteristics of split-brain patients, as described in this video by VS Ramachandran:
Not only do the separate hemispheres exhibit distinct personalities and beliefs, as Ramachandran explains; they even have separate wills. I described this in a comment at UD a few years ago:
Even stronger evidence against the dualist position is provided by split-brain patients. There is a procedure, the corpus callosotomy, that disconnects the two hemispheres so that epileptic seizures cannot spread from one to the other. The hemispheres are only disconnected; neither is removed. This operation contains the seizures, dramatically improving the patient’s quality of life, but it also severs the path through which the hemispheres normally communicate. The results are fascinating, and they’re not very friendly to the dualist position:
a. In experiments with split-brain patients, it’s possible to pass information to one hemisphere but not the other. The left hemisphere literally doesn’t know what the right hemisphere knows, and vice-versa.
If there were a single, immaterial mind, it would know what both hemispheres know. Clearly, this doesn’t happen. As a dualist, how do you explain this? Surely the immaterial mind doesn’t split in two at the moment the corpus callosum is cut, does it?
These fascinating videos of a split-brain patient demonstrate the phenomenon:
b. The left hemisphere controls the right half of the body, and vice-versa. When the connection between the two is cut, this results in bizarre behaviors indicating the presence of two “wills” in the same skull.
One patient was seen to pick up a cigarette with her right hand and place it in her mouth. Her left hand plucked it out and threw it away before the right hand could light it.
In another case, a man attacked his wife with one arm while defending her with the other.
If a single immaterial mind were running the show, this would not happen. How do you explain this within the dualist framework?
The question is just as relevant now as it was then. Dualists, how do you reconcile these phenomena with your worldview without twisting yourselves into logical pretzels?
So, what does that make you, keiths? A monist, a pluralist? Or something else otherwise (un)named?
Be careful re: cognitive studies or Denyse O’Leary will sic Mario Beauregard on ya! 😉
An Indian Brahmin who attended Trinity College, Cambridge and later became an atheist (or agnostic scientist) in the USA. An unusual story? “If you’re talking about God in some very abstract sense, like in India the Dance of Shiva or in the Spinoza sense of the word God, then I’ll say I have no problem with it.” – V. Ramachandran
Most Indians I’ve met are very ‘spiritual’ persons. If that makes them ‘dualists,’ then perhaps keiths will be against them or at least skeptical of them too. Or perhaps the point of this thread is keiths going ‘eastern’ with his worldview, apparently with the support of neuroscience?
Probably it’s all over my head! 😉
Your post doesn’t seem to be responsive to the questions posed by the OP.
Gregory,
I realize that this may disappoint you in your quest for drama, but this thread is merely about an idea (substance dualism) and its (in)ability to explain the data (observations of split-brain patients).
I just watched those two videos of Joe, the split-brain patient, for the first time since posting them at UD years ago. They still give me the chills.
I don’t see what you think the problem is, unless you think that “souls” are specific personalities, or that only one immaterial entity can operate one physical brain at a time.
I don’t consider the soul a personality – IMO, most “personality” resides in the body and in mind (mind is not soul). There is no limitation to how many personalities a soul can express through a material vehicle (brain), and there is no limit to how many souls (through mind) can be operating a single material vehicle – what we would call “possession”, or past life resurgence, or MPD.
This is the kind of result that supports the atheist worldview but theists have no trouble explaining away. They can claim that the patient whose 2 brain halves answered yes/no to believe in god was just being playful or perverse ( or one side of his brain was) They could claim that the split brain just divides higher level functions but each patient still has an underlying unitary whole.
Your evidence?
Ad hoc explanation means never having to admit being wrong.
There’s plenty evidence for non-local and survival of consciousness after death, from many sources – mediumship research, OOBE research, past life research, and NDE research. Whether or not one considers it valid or convincing is another matter.
Do you, personally, believe in ghosts William?
If this comment is in reply to the request for evidence for your claim that
Then obviously you personally find that evidence convincing.
Would that be correct? That you believe that there is no limit to how many souls (through mind) can be operating a single material vehicle because of the evidence you’ve seen from many sources for non-local and survival of consciousness after death?
A pattern seems to emerge./
William makes a claim.
William is asked to provide evidence for that claim.
William notes that there is plenty of evidence for his claim.
William notes that the evidence which exists may not be valid or convincing.
William has escaped from providing the evidence for his claim.
So, the obvious question is William, do you *personally* find the evidence for non-local and survival of consciousness after death valid or convincing?
If so, what is that evidence?
If not, on what basis do you make your claim that there is no limitation to how many personalities a soul can express through a material vehicle?
And in answer to your question on another thread, how do children learn, the answer is obvious. They don’t. They simply become better attuned to the soul that is possessing them. Under your “proposal” that is the most logical answer.
Mediumship research?
That he says it with a straight face is the most telling fact of them all.
In the UK mediums are now legally obligated to give a “disclaimer” that this is all “just for fun”. Yet in Williams world mediums are in fact conducting cutting edge research into the human condition.
William,
That is exactly what most substance dualists believe. The OP is directed at them.
I haven’t considered whether your own idiosyncratic belief system clashes with observations of split-brain patients in particular, though your insistence on an immaterial component of cognition certainly clashes with neuroscientific evidence generally.
Maybe dualism has some problems to explain all that experiences, but at the same light how can the “materialistic model of reality” can explain “human will” and “human freedom”? Do not show that experiences that our freedom and responsability is not more than an illusion?
Mediumship research was a legitimate field in the late 19th and early 20th century. A lot of people, including Houdini, participated. The results were a null set of positive evidence.
We may assume that result, but the research needed to be done.
Hi RodW,
Not as easily as you might think.
Did you watch the second and third videos? It’s clear that information directed to one hemisphere remains unknown to the other. You can’t be playful or perverse with information that you don’t have.
Yes, but if they do so they are admitting that those functions are carried out by the brain, not by the mind or soul.
If the brain, not the soul, is responsible for belief in God (or lack thereof), then why is the soul rewarded (or punished) for the brain’s belief?
In the case of the man who attacked his wife with one arm and defended her with the other, has the soul sinned? How can the soul be held morally responsible if the will belongs not to it, but to the brain (or in this case to each hemisphere of the brain)?
Dualists are stuck between a rock and a hard place:
1. They can admit that any function that differs between the two hemispheres is carried out by the brain, not the soul — but for most of them, that has dire consequences for their theology and for their arguments concerning moral responsibility.
2. They can assert that the immaterial soul splits into two at the moment the corpus callosum is cut. But why on earth should that happen?
Ramachandran is right: this information should send shockwaves through the theological community.
I’m very interested in hearing dualists explain how they can maintain their belief in dualism in the face of this overwhelming contrary evidence.
Well, yes, full explanations would be nice, which is why research is ongoing.
How much “free will and behavior” do you have if you are in a state of hypothermia or hyperthermia?
Do you understand the importance of the temperature dependence of consciousness?
Blas,
To say the least.
I don’t think materialism has any trouble explaining will and freedom, but that’s already being discussed in another thread. Let’s not derail this one.
I think that Murray has already supplied you with an answer: the mind is not the soul. Presumably a dualist could agree that “the mind is what the brain does” and just add the further caveat that the soul is something else altogether.
Though I’m not a dualist (or a materialist), I do think that there’s some deep insight in the thought that the mind and the soul are different — though not different things. Instead, the distinction expresses the fact that there’s a basic difference between the discourse of the soul, whether it takes an explicitly theological form or a more ‘humanistic’ form, and the discourse of the mind, which involves psychology and (increasingly) neuroscience. Conceivably, neuroscience could put psychology out of a job (though I doubt it), but neuroscience could not abolish literature, art, music, philosophy, and literary criticism — regardless of whether one adds theology and religion to that list.
Long ago, back in high school, a class mate was involved in a traffic accident and had significant brain injury. What was very noticeable to everyone, after he returned to school, was that his personality was substantially changed.
I suspect others have had similar experiences with friends and acquaintances.
So yes, the brain is intimately connected with who we are (with what some would call our souls).
Indeed, I looked into it a bit after that and it was quite interesting actually. All totally news to me. Following the evidence works!
I think there’s enough evidence to convince many reasonable people. Yes, I believe in ghosts and all sorts of spiritual phenomena. As far as enough evidence to convince me, I suppose there would be enough if I that was how I went about choosing my beliefs.
Arguing for or against dualism based on how people act here, including the video, requires that one accept a certain set of descriptions as “true” when it comes to what the spiritual world is and how it interacts with the physical. Keith’s argument that dualism has a hard time explaining that which is demonstrated by the video is like Darwin or darwinists claiming that intelligent design or creationism has a hard time explaining a deadly virus or what they call “imperfect” design.
There really isn’t a problem with dualism accommodating what we see in the video – or any other such evidence – the only problem is that it doesn’t fit in with keith’s preconceived notion of the rules supposedly governing dualistic interactions and his preconceived notions about how spiritiual phenomena should behave.
Actually, what I meant is that there is ongoing scientific research into mediumship, not that mediums are conducting research.
Presumably demon possession is one of those phenomena? After all, if there is no limitation to how many personalities a soul can express through a material vehicle (brain), and there is no limit to how many souls (through mind) can be operating a single material vehicle then perhaps The Exorcist was a documentary after all!
Any recent research results supporting mediumship as a real thing then?
If you can’t point to any, and I doubt that you’ll be able to, why do you believe in it? Seems your “bonus” free will just makes you appear irrational.
It’s easy enough to find recent mediumship research if you just google it. Julie Beischel & Gary E. Schwartz have done a lot of work in this area, including refining research techniques.
You forget that I believe whatever I want to believe, whether there is evidence to support it or not. If I wish to believe in spirits, ghosts and demonic possession, I’m free to. Such beliefs do not directly contradict anything I experience.
William J. Murray said:
You forget that I believe whatever I want to believe, whether there is evidence to support it or not.
What else is new?
Kantian Naturalist,
But William thinks the mind is immaterial, and that it performs feats that are out of reach for ‘mere’ physical systems like the brain. In any case, William’s ideas are a jumble, and as he cheerfully admits, they are unconstrained by evidence.
I am far more interested in the thinking of those dualists who, unlike William, actually care whether their ideas are true. For example, many Christians believe in a soul that survives death and is rewarded or punished for its actions and beliefs during its time on earth. The truth of that belief is very important to them. How can it be reconciled with what we know about split-brain patients?
William,
I’m interested in what most substance dualists actually believe, and how they reconcile it with the evidence.
As I clearly stated in the OP:
If this immaterial ‘true self’ is the site of our will, our beliefs, our moral responsibility, our rationality, etc., as most substance dualists believe, then why does cutting the corpus callosum cleave this ‘true self’ in two? And if it does not, then how do dualists explain the divergent knowledge, beliefs, wills, and actions of the two hemispheres?
Note to participants: I have changed the title of the OP for the benefit of readers who are unfamiliar with the term ‘substance dualism’.
It now reads:
Split-brain patients and the dire implications for the soul
Can you not envisage some dystopian futures where neuroscience is the means by which all these pursuits lose relevance?
“The question is just as relevant now as it was then. Dualists, how do you reconcile these phenomena with your worldview without twisting yourselves into logical pretzels?”
Simple. Possession. If spirits exist, its a no-brainer.
And to answer the ‘Do spirits exist and show me your proof?” follow-up question, the Vatican has a vast store of supporting evidence for the existence of spirits in their experience with exorcisms.
It all comes down to the I.
If there is no I, then stop talking to yourself, dammit. And stop telling your body what to do. Sheesh.
Seriously, Steve?
You’re arguing that every time a person’s corpus callosum is cut, a spirit swoops in and takes possession of one of the brain’s hemispheres?
How does that work? And can you explain how an intact corpus callosum protects its owner from being possessed by spirits?
It is impossible to tell if you are joking, Steve.
Spirit possession is temperature dependent; especially as the core body temperature rises above 106 degrees Farhenheit.
Below 60 Fahrenheit, spirits can’t infest the body and push it around; too hard.
These are vague examples. Nothing to make a case on.
Belief/unbelief need only only be indecision revealed in some person. like many people without a more profound sense of segregation of thoughts.
The videos only show how people draw conclusions.
It shows nothing about the soul or against it.
The soul just reads information. No different then eyesight.
Being blind stops a soul from seeing but only because of the connection of the immaterial soul with the material world.
All these things was about seeing things.
In fact it hints at a unified soul able to read different info while not in other ways reading it.
The soul was not deceived but just the machine of communication.
.In fact i think it could all just show its the memory that is the only thing going on about results. further how eyesight workd might be hinted at.
Nothing here against the soul.
I can easily imagine a dystopian future in which a totalitarian government, determined to stifle imagination and thought, uses neuroscience in some way or other in order to attack art, literature, music, and philosophy. So ‘yes’. But then the root of the evil does not lie in what neuroscience says about our brains (or about ‘us’), but in what totalitarian governments do with that research. In a genuine utopia, neuroscience would be no threat at all to imagination and thought — quite the opposite.
I was thinking not to attack so much, as replace. My point is that it is *not* inconceivable that neuroscience could make those things redundant. Maybe some kind of direct brain stimulation. We could perhaps have an experience that does whatever listening to music does for us without ever hearing any music.
I don’t mean this as a warning about neuroscience in the slightest. My thrust is that it is not so easy to predict the future, what can be achieved by a field. Dystopian futures are just the most easily conceivable examples.
Perhaps what we now wish to be true, that art is irreplaceable, affects what we think must be true.
Some UDers have responded to this OP on their home turf, starting here.
Ever seen a ghost William? Please, do tell!
Not sure this belongs here or in another thread, but I’ll plop it here for the time being. I’m not a dualist. I used to believe in “souls”, “spirits”, and the supernatural, but over time I’ve found those concepts to be vague and, in most theistic forms, incompatible with physics. A monistic, material conceptualization of self and body makes more sense to me.
One thing I still puzzle over however is the concept of what I call perspective. In other words the view of the world from “my” perspective as opposed to the view of the world through what I term “other” perspectives.
Assuming for the sake of argument that the world/reality I perceive is not an illusion or some entertainment created specifically for me, every other organism out in the world represents some “other perspective” on the world and universe. There are literally billions upon billions of other perspectives. The question I ask myself is two fold: why is there a “my” perspective and what determines any given perspective.
Note, perspective and personality are not synonymous here. What I’m addressing is related to Barry’s homunculus looking out through my eyes. And what I’m asking is less abstract than “why am I here”. Rather I am asking, “is there a probabilistic or physical correlation between matter condensation and given perspectives.
In other words, given that in this universe there is finite matter and that this universe theoretically has a limited duration, it follows that given perspectives are finite as well. If that is the case, is it a given that every possible perspective in this universe MUST arise at some point during this universe’s existence? And if that is the case, is perspective tied to specific material configurations. If so, does this mean that the Hindus have the right idea and that given perspectives are probabilistically recycled over and over and over again?
Oh…I should add – this concept occurred to me because I could not reconcile the idea of my existence with a vastly huge number of possible perspectives. In other words, given the universe operates just fine with billions upon billions upon billions of organisms with perspectives that are not “my” view on the world, it’s reasonable to conclude that the universe would operate just fine if there was no organism with “my” perspective. And given the odds of “my” perspective coming up once in a universe for which a near infinite number of possible perspectives could exist, it seems improbable. However, if there are a limited number of perspectives and they must all come up a number of times given the odds of certain material arrangements coming up, that seems more plausible.
Of course, none of the reoccurring perspectives would have any recollection of any previous occurrence since there would be no substrate for memory retention, so maybe it’s a moot point.
I think the flame metaphor is apt.
I’m not sure if I know the flame metaphor. What is that?
It’s not a matter of what you believe or not, it’s what you advocate to others. I’d expect that advocacy would require a bit more than “I believe it for no discernable reason, therefore you should as well”.
It’s a phenomenon like a holographic photo. If you break this holographic photo in smaller pieces, in every smaller piece there is the whole photographed scene – though smaller.
The seemingly contradictory behaviour of the patients – left against right or vice versa – and the lack of bewareness of the other one, or other half, is no proof that there ain’t a soul.
If there could be shown persons, who were running around with a triple sected brain resulting in the existence of three persons not being aware of each other, and if you could show me persons with quadruple sected brains resulting in the existence of four persons not being aware of each other – etc. pp. well, then it would proof nothing at all.
All that is proved is that if you cut people’s brains in the described way, there are multiple personalities.
Multiple personalities do not proof that the soul does not exist.
It just does not refer to anything unvisible.
The Wilder Penfield experiments show the exact opposite of these experiments you show. But all experiments refer to the brain as the visible world – not to the invisible world.
So you cannot proof anything with these experiments and you will have to wait until death shows you. On that. I do agree.
You can’t prove a negative. I’m not aware of any soul advocates predicting these results. That’s really the issue.
someone else,
Did you see the argument I presented at UD?